工艺因素对C／C复合材料ICVI致密化的影响

Influence of the Factors of CVI Technology on Densification of C/C Composites

以2D针刺碳毡为预制体、丙烯为前驱气体、氮气为稀释气体,在常压条件下研究了沉积温度、滞留时间和丙烯分压等工艺因素对致密化速度的影响。结果表明,三个工艺参数协同作用,对致密化具有相似的影响:参数取值较高时初期致密化速度也较快,结果导致预制体表层气孔的过早填充,不利于进一步的沉积,反之,则致密化速度较慢,但有利于预制体内部的沉积。

Under atmospheric pressure, the effect of different factors, such as residence times and various deposition temperatures and the partial pressure of precursor on the densification rate was investigated. Propylene is applied as the precursor while nitrogen and the 2D carbon felt are the dilute gas and the perform, respectively. The result illustrates that three factors have similar effects on densification： the relatively quick densification rate is seen when these factors at the high value resulting in early fill in pore on preform surface. This is not good for further densification. In contrast, the deposition rate is slow at the low value while it is good for the inner deposition of the preform.